With the help of Megara, Cylon seized the Acropolis but was defeated. The execution of his companions while they were suppliants at an altar was caused by the archon Megacles, who thus attached a permanent curse on his family (the Alcmaeonidae).
Bouchard, Elsa. "Failed attempt at tyranny by Cylon at Athens". The Literary Encyclopedia. First published 01 March 2010
[http://www.litencyc.com/php/stopics.php?rec=true&UID=11153, accessed 19 December 2014.]